12 
COLORADO EXPERIMENT STATION 
for the destruction of the eggs except when applied so strong as to make 
it entirely impractical to use it. 
The Lime-Sulfur Mixtures —Either the 1-1-2, or the 1-1-3 
formula or Rex lime-sulfur in dilutions down to i gallon in 8 gallons of 
water, have given good results. Lime-sulfur by the 1-1-4 formula is a little 
weak for good results. 
Black Leaf —This preparation used in the proportion of i gallon 
in 25, and i gallon in 33 of water gave good results, but i gallon in 40 gal¬ 
lons of water was not very satisfactory, many of the eggs hatching. 
summe:r spraying 
For the destruction of the lice upon the leaves spray very thoroughly 
and forcefully from all directions with kerosene emulsion, 5 to 7 per cent, 
oil; Black Leaf, i part in 70 parts of water; or one of the other plant louse 
sprays discussed at the close of this bulletin, remembering that thorough and 
forceful applications are necessary in order to get best results. 
PEACH PLANT LICE. 
There are two species of plant lice attacking peach trees in Colorado, 
the Green Peach Aphis {^Myzus persicae SuIb.') and the Black Peach 
Aphis {Aphis persicae-niger Smith.) The iformer is very generally dis¬ 
tributed and occurs nearly every where that this fruit is grown, while the 
latter occurs in isolated orchards only, and might be kept down so as to do 
no appreciable harm, and it is quite possible that it might be practical to 
exterminate it from the state. 
THE GREEN PEACH APHIS 
Is distinguished by its pale green, or greenish yellow color in the wing¬ 
less forms and the winged lice have the same general ground color to their 
bodies with more or less of black markings above. 
The lice appear very early in the spring and often attack the blossoms, 
and the young peaches when the latter first form, causing them to wilt and 
drop. Later it attacks the leaves causing them to curl and turn yellow. 
By the middle of the summer this louse leaves the peach trees and goes 
to cabbages, turnips, radishes, tomatoes, potatoes and many other growing 
crops, as well as many of the common weeds. The lice remain upon these 
plants during the summer and in the fall there are winged forms that re¬ 
turn to the peach to give birth to true males and females, the latter of 
which deposit the eggs that remain upon the twigs of the trees during win¬ 
ter to hatch out the early lice of the following spring. 
• REMEDIES 
Spray thoroughly with kerosene emulsion. Black Leaf (i part in 60 of 
water), or a solution of whale-oil soap (i pound to 6 gallons of water), 
about three or fo.ur days before the blossoms open. Then, if the lice ap¬ 
pear later, treat as in case of the green apple aphis. 
THE BLACK PEACH APHIS 
This louse is readily distinguished from any other attacking the peach 
